package com.lagou.factory;

import com.lagou.annotion.MyAutowired;
import com.lagou.annotion.MyService;
import com.lagou.utils.TransactionManager;
import org.springframework.cglib.proxy.Enhancer;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

/**
 * @Author ZHAO Yudong
 * @Date 2020/11/6 14:42
 * @description：
 */
@MyService("proxyFactory")
public class ProxyFactory {

	@MyAutowired
	private TransactionManager transactionManager;

	public void setTransactionManager(TransactionManager transactionManager) {
		this.transactionManager = transactionManager;
	}

	/**
	 * Jdk动态代理
	 */
	public Object getJdkProxy(Object obj) {
		// 获取代理对象
		return Proxy.newProxyInstance(obj.getClass().getClassLoader(), obj.getClass().getInterfaces(),
			new InvocationHandler() {
				@Override
				public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
					Object result = null;
					try {
						// 开启事务(关闭事务的自动提交)
						transactionManager.beginTransaction();
						result = method.invoke(obj, args);
						// 提交事务
						transactionManager.commit();
					} catch (Exception e) {
						e.printStackTrace();
						// 回滚事务
						transactionManager.rollback();
						// 抛出异常便于上层servlet捕获
						throw e;
					}
					return result;
				}
			});
	}

	/**
	 * 使用cglib动态代理生成代理对象
	 */
	public Object getCglibProxy(Object obj) {
		return Enhancer.create(obj.getClass(), new MethodInterceptor() {
			@Override
			public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
				Object result = null;
				try {
					// 开启事务(关闭事务的自动提交)
					transactionManager.beginTransaction();
					result = method.invoke(obj, objects);
					// 提交事务
					transactionManager.commit();
				} catch (Exception e) {
					e.printStackTrace();
					// 回滚事务
					transactionManager.rollback();
					// 抛出异常便于上层servlet捕获
					throw e;
				}
				return result;
			}
		});
	}
}
